Is there an snmp program with graphing capability?

I am looking for an snmp program with graphing capability. I am not sure if there is one (something like cacti or bb?)

I found one (payed only)from ireasoning.com, but I am not sure if there is a opensource package that can do the same. The free version cannot graph anything, but the payed version can.

Cacti and bb can do anything I want, but I am looking for a portable program with such capability.

Thanks in advance.